Finished DNS-SD server. Finished Privet-specified DNS-SD server.

cloud_print/gcp20/prototype/printer.cc

+// Copyright 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "cloud_print/gcp20/prototype/printer.h"
+
+#include <ifaddrs.h>
+#include <netdb.h>
+
+#include "base/command_line.h"
+#include "base/strings/string_number_conversions.h"
+#include "cloud_print/gcp20/prototype/dns_txt_builder.h"
+#include "cloud_print/gcp20/prototype/service_parameters.h"
+
+namespace {
+
+const char* kServiceType = "_privet._tcp.local";
+const char* kServiceNamePrefix = "first_gcp20_device";
+const char* kServiceDomainName = "my-privet-device.local";
+
+const uint16 kDefaultTTL = 60*60;
+const uint16 kDefaultHttpPort = 10101;
+
+uint16 ReadHttpPortFromCommandLine() {
+  uint32 http_port_tmp = kDefaultHttpPort;
+
+  std::string http_port_string_tmp =
+      CommandLine::ForCurrentProcess()->GetSwitchValueASCII("http-port");
+  base::StringToUint(http_port_string_tmp, &http_port_tmp);
+
+  if (http_port_tmp > kuint32max) {

[gene, 2013/06/19 05:40:51]

I think max port number in TCP and UDP is 64k

[maksymb, 2013/06/19 21:47:21]

Yes, this is right. Fixed.

+    LOG(ERROR) << "Port " << http_port_tmp << " is too large (maximum is " <<
+        kDefaultHttpPort << "). Using default port.";
+
+    http_port_tmp = kDefaultHttpPort;
+  }
+
+  VLOG(1) << "HTTP port for responses: " << http_port_tmp;
+  return static_cast<uint16>(http_port_tmp);
+}
+
+uint16 ReadTtlFromCommandLine() {
+  uint32 ttl = kDefaultTTL;
+
+  base::StringToUint(
+      CommandLine::ForCurrentProcess()->GetSwitchValueASCII("ttl"), &ttl);
+
+  VLOG(1) << "TTL for announcements: " << ttl;
+  return ttl;
+}
+
+// Returns pointer to local IP address number. Examples for interface name
+// are: "wlan0", "eth0", NULL (find first acceptable except "lo").
+net::IPAddressNumber GetLocalIp(const char* interface_name) {
+  net::IPAddressNumber result;  // |result| is empty if no interface found.
+
+  ifaddrs* first_interface = NULL;
+  if (getifaddrs(&first_interface) == -1) {
+    LOG(ERROR) << "getifaddrs() failed";
+    return result;
+  }
+
+  // Browse all interfaces.
+  char host[NI_MAXHOST] = {0};
+  for (ifaddrs* interface = first_interface; interface;
+       interface = interface->ifa_next) {
+    if (!interface->ifa_addr)
+      continue;
+
+    // Get additional info about current interface.
+    int rv = getnameinfo(interface->ifa_addr, sizeof(*interface->ifa_addr),
+                         host, NI_MAXHOST, NULL, 0, NI_NUMERICHOST);
+
+    if (interface->ifa_addr->sa_family == AF_INET) {
+      // Find interface we need.
+      if (interface_name ? (strcmp(interface->ifa_name, interface_name) == 0)
+                         : (strcmp(interface->ifa_name, "lo") != 0)) {
+        if (rv != 0) {
+          LOG(ERROR) << "getnameinfo() failed: " << gai_strerror(rv);
+          break;
+        }
+
+        net::ParseIPLiteralToNumber(host, &result);
+      }
+    }
+  }
+
+  // Erase memory under list of interfaces.
+  freeifaddrs(first_interface);
+  return result;
+}
+
+}  // namespace
+
+Printer::Printer() : initialized_(false) {
+}
+
+Printer::~Printer() {
+  Stop();
+}
+
+bool Printer::Start() {
+  if (initialized_)
+    return true;
+
+  // TODO(maksymb): Add possibility to control interface via command line args.
+  net::IPAddressNumber ip = GetLocalIp(NULL);
+  if (ip.empty()) {
+    LOG(ERROR) << "No local IP found. Cannot start printer.";
+    return false;
+  }
+  VLOG(1) << "Local address: " << net::IPAddressToString(ip);
+
+  // Starting DNS-SD server.
+  initialized_ = dns_server_.Start(
+      ServiceParameters(kServiceType,
+                        kServiceNamePrefix,
+                        kServiceDomainName,
+                        ip,
+                        ReadHttpPortFromCommandLine()),
+      ReadTtlFromCommandLine(),
+      CreateTxt());
+
+  return initialized_;
+}
+
+void Printer::Stop() {
+  if (!initialized_)
+    return;
+
+  dns_server_.Shutdown();
+}
+
+std::string Printer::CreateTxt() const {
+  DnsTxtBuilder txt_builder;
+
+  txt_builder.AddRecord("txtvers=1");
+  txt_builder.AddRecord("ty=Google Cloud Ready Printer GCP2.0 Prototype");
+  txt_builder.AddRecord("note=Virtual printer");
+  txt_builder.AddRecord("url=https://www.google.com/cloudprint");
+  txt_builder.AddRecord("type=printer");
+  txt_builder.AddRecord("id=");
+  txt_builder.AddRecord("cs=offline");
+
+  return txt_builder.Build();
+}
+